CVE-2018-5733 - CVE House
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Status published Medium CVE-2018-5733

A malicious client can overflow a reference counter in ISC dhcpd

Vulnerability Description

A malicious client which is allowed to send very large amounts of traffic (billions of packets) to a DHCP server can eventually overflow a 32-bit reference counter, potentially causing dhcpd to crash. Affects ISC DHCP 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8, 4.3.0 -> 4.3.6, 4.4.0.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • ISC would like to thank Felix Wilhelm, Google Security Team, for reporting this vulnerability.

References

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Affected Vendor

Affected Software

ISC DHCP
Vulnerable Versions:
ISC DHCP 4.1.0 -> 4.1-ESV-R15, 4.2.0 -> 4.2.8, 4.3.0 -> 4.3.6, 4.4.0

Timeline

Official Publish: January 16th, 2019
Last Modified: April 25th, 2025
Added to House: July 20th, 2026

CVSS Vectors

V3: CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.